Murphy framed the gun debate as a chance for Republicans to prove that they can work with Democrats to pass legislation, avoiding the need to eliminate the Senate filibuster, as some Democrats have urged. If 60 senators join forces to approve expanded background checks, Murphy said, that could create an opening to cooperate on other matters.

“Once we convince Republicans that the sky doesn’t fall for you politically when you support a reasonable expansion of something like background checks, you can move on to other interventions,” Murphy said.

Murphy acknowledged that gun bills approved by the House earlier this month could not survive in the Senate without substantial changes. The House bills would expand background checks to include private transactions between unlicensed individuals and close a loophole that allows gun sales to go through after three business days even if the background check is incomplete. Those provisions lack support among even some moderate Democrats in the Senate and could not garner the 60 votes needed to overcome a potential GOP filibuster.